Potential Function Describing the Folding of the 30 nm Fiber

Potential Function Describing the Folding of the 30 nm Fiber

Most of the DNA in a eucaryotic cell nucleus is accurately described as an extremely long thin fiber which is smoothly folded by histones into a thicker fiber called the 30 nm fiber. For the DNA to remain biologically functional, the 30 nm fiber must be only marginally stable. Therefore, we assume that the 30 nm fiber has fluidlike properties under physiologic conditions. It does not possess a ...

Chromatin without the 30-nm fiber

Internal structure of the 30 nm chromatin fiber.

In the presence of 1.7 mM Mg2+, the diameter of the circular structures produced by small chromatin fragments isolated from chicken erythrocytes remains essentially unchanged when the number of nucleosomes in these fragments increases from 10 to 36. In contrast, the results obtained in unidirectional shadowing experiments show that under the same conditions the height of the chromatin fragments...

Higher-Order Structures of Chromatin: The Elusive 30 nm Fiber

Despite progress in understanding chromatin function, the structure of the 30 nm chromatin fiber has remained elusive. However, with the recent crystal structure of a short tetranucleosomal array, the 30 nm fiber is beginning to come into view.

Theory and computational modeling of the 30 nm chromatin fiber

Introduction For its fundamental importance in gene regulation and epigenetics, the physical chemistry of structural changes in the chromatin fiber has become a major focus of interest in recent years. It is now clear that the mechanism of chromatin remodeling, opening and closing of the structure during transcription, and many other biological processes related to the higher order structure of...